| Structural highlights
6qtn is a 6 chain structure with sequence from [1] and Bos taurus. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
| | Ligands: | , , , , , , , , |
| Resources: | FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT |
Function
[TBA1B_BOVIN] Tubulin is the major constituent of microtubules. It binds two moles of GTP, one at an exchangeable site on the beta chain and one at a non-exchangeable site on the alpha chain. [STMN4_RAT] Exhibits microtubule-destabilizing activity.[1] [2] [3] [TBB2B_BOVIN] Tubulin is the major constituent of microtubules. It binds two moles of GTP, one at an exchangeable site on the beta chain and one at a non-exchangeable site on the alpha chain (By similarity).
Publication Abstract from PubMed
It has been proposed that one of the mechanisms of taxane-site ligand-mediated tubulin activation is modulation of the structure of a switch element (the M-loop) from a disordered form in dimeric tubulin to a folded helical structure in microtubules. Here, we used covalent taxane-site ligands, including cyclostreptin, to gain further insight into this mechanism. The crystal structure of cyclostreptin-bound tubulin reveals covalent binding to betaHis229, but no stabilization of the M-loop. The capacity of cyclostreptin to induce microtubule assembly compared to other covalent taxane-site agents demonstrates that the induction of tubulin assembly is not strictly dependent on M-loop stabilization. We further demonstrate that most covalent taxane-site ligands are able to partially overcome drug resistance mediated by betaIII-tubulin (betaIII) overexpression in HeLa cells, and compare their activities to pironetin, an interfacial covalent inhibitor of tubulin assembly that displays invariant growth inhibition in these cells. Our findings suggest a relationship between a diminished interaction of taxane-site ligands with betaIII-tubulin and betaIII tubulin-mediated drug resistance. This supports the idea that overexpression of betaIII increases microtubule dynamicity by counteracting the enhanced microtubule stability promoted by covalent taxane-site binding ligands.
Crystal Structure of the Cyclostreptin-Tubulin Adduct: Implications for Tubulin Activation by Taxane-Site Ligands.,Balaguer FA, Muhlethaler T, Estevez-Gallego J, Calvo E, Gimenez-Abian JF, Risinger AL, Sorensen EJ, Vanderwal CD, Altmann KH, Mooberry SL, Steinmetz MO, Oliva MA, Prota AE, Diaz JF Int J Mol Sci. 2019 Mar 20;20(6). pii: ijms20061392. doi: 10.3390/ijms20061392. PMID:30897704[4]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Nakao C, Itoh TJ, Hotani H, Mori N. Modulation of the stathmin-like microtubule destabilizing activity of RB3, a neuron-specific member of the SCG10 family, by its N-terminal domain. J Biol Chem. 2004 May 28;279(22):23014-21. Epub 2004 Mar 22. PMID:15039434 doi:http://dx.doi.org/10.1074/jbc.M313693200
- ↑ Gavet O, El Messari S, Ozon S, Sobel A. Regulation and subcellular localization of the microtubule-destabilizing stathmin family phosphoproteins in cortical neurons. J Neurosci Res. 2002 Jun 1;68(5):535-50. PMID:12111843 doi:http://dx.doi.org/10.1002/jnr.10234
- ↑ Ravelli RB, Gigant B, Curmi PA, Jourdain I, Lachkar S, Sobel A, Knossow M. Insight into tubulin regulation from a complex with colchicine and a stathmin-like domain. Nature. 2004 Mar 11;428(6979):198-202. PMID:15014504 doi:http://dx.doi.org/10.1038/nature02393
- ↑ Balaguer FA, Muhlethaler T, Estevez-Gallego J, Calvo E, Gimenez-Abian JF, Risinger AL, Sorensen EJ, Vanderwal CD, Altmann KH, Mooberry SL, Steinmetz MO, Oliva MA, Prota AE, Diaz JF. Crystal Structure of the Cyclostreptin-Tubulin Adduct: Implications for Tubulin Activation by Taxane-Site Ligands. Int J Mol Sci. 2019 Mar 20;20(6). pii: ijms20061392. doi: 10.3390/ijms20061392. PMID:30897704 doi:http://dx.doi.org/10.3390/ijms20061392
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